U.S. patent application number 14/282675 was filed with the patent office on 2015-01-15 for cooling roof construction.
This patent application is currently assigned to EXCELLENT HOLDING APS. The applicant listed for this patent is EXCELLENT HOLDING APS. Invention is credited to Ole FREDERIKSEN.
Application Number | 20150017907 14/282675 |
Document ID | / |
Family ID | 50732077 |
Filed Date | 2015-01-15 |
United States Patent
Application |
20150017907 |
Kind Code |
A1 |
FREDERIKSEN; Ole |
January 15, 2015 |
COOLING ROOF CONSTRUCTION
Abstract
A cooling roof construction comprising a substantially
horizontal roof having a weatherproof membrane, and where a
perforated tile layer is arranged a distance above said membrane,
where the space between the membrane and the perforated tile layer
is connected by at least one conduit to an outside ambient
space.
Inventors: |
FREDERIKSEN; Ole; (Hornslet,
DK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EXCELLENT HOLDING APS |
Morke |
|
DK |
|
|
Assignee: |
EXCELLENT HOLDING APS
Morke
DK
|
Family ID: |
50732077 |
Appl. No.: |
14/282675 |
Filed: |
May 20, 2014 |
Current U.S.
Class: |
454/284 ;
52/302.1 |
Current CPC
Class: |
F24F 7/02 20130101; E04D
13/172 20130101; F24F 2005/0082 20130101; E04D 11/005 20130101;
E04D 1/30 20130101 |
Class at
Publication: |
454/284 ;
52/302.1 |
International
Class: |
E04D 13/17 20060101
E04D013/17; F24F 7/02 20060101 F24F007/02; E04D 1/30 20060101
E04D001/30 |
Foreign Application Data
Date |
Code |
Application Number |
May 22, 2013 |
DK |
PA 2013 70274 |
Claims
1. A cooling roof construction comprising a substantially
horizontal roof having a weatherproof membrane, and where a
perforated tile layer is arranged a distance above said membrane,
where the space between the membrane and the perforated tile layer
is connected by at least one conduit to an outside ambient space
outside the roof's perimeter or above the tile layer.
2. The cooling roof construction according to claim 1 wherein the
perforated tile layer is assembled from a plurality of tiles, where
the tiles are elevated relative to the membrane by means of
risers.
3. The cooling roof construction according to claim 2 wherein the
risers have different height, such that the tile layer is a slanted
or horizontal surface.
4. The cooling roof construction according to claim 1 wherein the
ambient space to which the conduit is connected is at a lower
elevation or cooler space than the space between the membrane and
the tile layer.
5. The cooling roof construction according to claim 1 wherein the
tiles and/or risers are made from plastics, preferably in an
injection moulding process.
6. The cooling roof construction according to claim 1 wherein
temperature controlled valve means are provided near the outlet of
the conduit.
7. Method of cooling a building having a substantially flat roof
space, where at least one perforated tile is arranged at a distance
above the roof, and where cooler air by means of a conduit is
guided into the space created between the roof and the perforated
tile.
8. Method according to claim 7 wherein the cooler air is obtained
from a lower elevation, a cellar space, a well or the like, and by
natural convection transported to the space between the roof and
the perforated tile, where the cooler air is heated due to the
exposure to solar heating of the tile surface, where after the air
escapes upwards through the perforations in the tiles creating
under-pressure in the space between the roof and the tiles, thereby
creating air movement.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Danish Patent
Application No. PA 2013 70274 filed on May 22, 2013, the entire
contents of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a cooling roof construction
as well as a method of cooling buildings utilizing such a roof
construction.
BACKGROUND OF THE INVENTION
[0003] With the increasing focus on energy consumption there is a
desire to lower the energy consumption and thereby the cost of
energy in connection with among other things buildings, living
quarters, etc.
[0004] For houses the object is to maintain an interior climate
which is neither too cold nor too hot and as such during winter
periods it is necessary to heat the houses and during summer
periods it is desirable to cool the houses. In a number of regions
the costs of cooling houses exceed by far the costs of heating
houses. Furthermore, it is more energy consuming to cool the
interior of houses than it is to heat the same house.
[0005] It is known in the art to provide a perforated upper roofing
layer, see for example U.S. Pat. No. 4,674,249. This construction
is provided in order to decrease damage to underlying roofing
constructions, and to further provide ventilation to the underlying
roof construction, for example in order to remove water ingressed
into the underlying structure.
OBJECT OF THE INVENTION
[0006] The present invention provides a low cost solution,
especially for cooling of houses. The invention is especially used
for buildings having a flat or substantially flat roof. The
invention is based on the principle that the sun will heat the flat
roof surfaces whereby the solar heating will penetrate the roof
construction and into the building thereby increasing the interior
temperature.
DESCRIPTION OF THE INVENTION
[0007] In this connection the invention provides a cooling roof
construction comprising a substantially horizontal roof having a
weatherproof membrane, and where a perforated tile layer is
arranged a distance above said membrane, where the space between
the membrane and the perforated tile layer is connected by at least
one conduit to an outside ambient space outside the roof's
perimeter or above the tile layer.
[0008] Be creating a perforated tile area arranged a distance above
the roof construction as such a space between the roof construction
and the perforated tiles is created. The air inside this space will
be heated by the solar influx, i.e. solar energy and due to the
basic principles of hot air rising relative to cooler air the air
in the space will move upwards, i.e. away from the roof surface
through the perforations in the tiles. During this movement an
under-pressure will occur between the perforated tiles and the roof
surface which will cause fresh air to be sucked into the space. As
this air has not been heated by the solar influx, the net result
will be that air in the space will have a substantially lower
temperature than air immediately above a fully exposed roof
surface. Therefore, the perforated tile layer will create a cooling
mechanism whereby the solar influx, i.e. the solar energy, will not
be able to penetrate into the roof construction and thereby heat
the interior of the building.
[0009] Furthermore by directing the conduit to be connected to an
ambient space, for example the free air on the side of the
building, the space between the roofing membrane and the tiles is
provided with fresh air, and not recirculation of the air "trapped"
in the space between the roofing membrane and the tiles. In this
manner, better ventilation and thereby cooling is achieved.
[0010] In a further advantageous embodiment the perforated tile
layer is assembled from a plurality of tiles, where the tiles are
elevated relative to the membrane by means of risers.
[0011] By using a plurality of tiles the elevated tile layer is
relatively easy to install in that it is possible to select tiles
which have a size which may easily be carried and manually handled
on the roof surface. Examples of such tiles are disclosed in U.S.
Pat. No. 5,509,244 but it should be understood that naturally the
invention is not limited to the use of this type of tiles, but
tests clearly indicate that these tiles are very useful for
obtaining the cooling properties of the present invention.
[0012] One further advantage of using tiles as suggested in U.S.
Pat. No. 5,509,244 is the size of the perforations. Naturally other
tiles having substantially corresponding perforation sizes may also
be used. The perforations has a size such that when snow falls on
the tiles, the snow will accumulate on the top side of the tiles,
leaving the space between the roof structure and the tiles free
from snow. This space will contain an amount of non-moving air,
which effectively will act as extra insulation. Consequently,
during hot periods, cool air will be provided helping to cool the
building whereas during cold periods with snow fall, the snow will
help insulate the building. Both situations will decrease the
energy needed to respectively cool or heat the building.
[0013] In the same context risers as suggested in EP1192323 may
also be used with good results. The advantages of using the risers
in the European patent provides the elevated layer with large
versatility in that different tile sizes may be used and the tile
layer may be arranged horizontally regardless of the slant of the
underlying roof structure, naturally within limits, simply by using
more or less risers. In this manner it is possible to convert a
relatively useless slanting/flat roof into a useful outdoor
space.
[0014] In a further advantageous embodiment of the invention the
risers have different height, such that the tile layer is a slanted
or horizontal surface. These advantages are already described above
and the risers may be constructed as suggested above by superposing
a plurality of riser elements or by manufacturing risers as single
elements having various heights. In a further advantageous
embodiment of the invention the ambient space to which the conduit
is connected is at a lower elevation or cooler space than the space
between the membrane and the tile layer. As an under-pressure is
created due to the solar energy heating the air trapped between the
perforated tile layer and the roof construction air movement is
created by the influx of solar energy. By connecting a conduit to
the air volume between the perforated tile layer and the roof
construction the air movement will cause air movement in the
conduit. By connecting the other end of the conduit to a place with
cooler air for example at a lower elevation or a cooler space such
as for example an area which will be in shadow or a cellar space,
ground well or the like, cooler air will be sucked into the space
between the perforated tile layer and the roof construction and as
such will further improve the lowering of the temperature on the
roof and thereby the influx of heat into the interior of the
building which will again lower the cost of cooling the interior of
the building.
[0015] In a further advantageous embodiment of the invention the
tiles and/or risers made from plastics, preferably in an injection
moulding process. By using the risers and tiles suggested above
these are plastic moulded elements which are constructed such that
they will be able to provide the necessary load carrying
characteristics in order to provide a useful surface. However, this
is not necessary in all instances and as such also weaker tile
elements and smaller risers may be used in order to provide the
same advantages as already described above. The injection moulding
process is a relatively cheap manufacturing process and as such
together with the relatively low cost of installing such a roof an
over-all cheap but very effective cooling installation may be
achieved.
[0016] In a still further advantageous embodiment temperature
controlled valve means are provided near the outlet of the
conduit.
[0017] The means for controlling the valves may be but not limited
to metal springs which are made from materials having specific
temperature expansion/contraction properties, such as the valves
are set to remain closed and only open when the temperature in the
volume between the roof and the tiles rises above 20 degrees
centigrade. The valves themselves may be simple dampers, plates or
the like which may be brought from a position obstructing the
conduit to a position where the air may flow freely through the
conduit, and any position in between.
[0018] The present invention is also directed to a method of
cooling a building using a cooling roof construction as already
described above. Naturally the advantages already discussed above
will also be achieved with the method.
DESCRIPTION OF THE DRAWING The invention will now be described with
reference to the accompanying drawings where
[0019] FIG. 1 illustrates a schematic cross-section through a roof
structure of a building.
DETAILED DESCRIPTION OF THE INVENTION
[0020] In FIG. 1 is illustrated a schematic cross-section through a
roof structure of a building. The building 1 in this embodiment has
a substantially flat roof structure 2. The roof structure is
provided with the normal membranes etc. in order to render it
watertight. These features are not illustrated as they are not
important for the invention.
[0021] Above the roof structure 2 is arranged a number of
perforated tiles 3 which tiles 3 are elevated relative to the roof
structure by means of risers 4. In this embodiment the risers 4 are
illustrated as comprising a number of superposed elements, but they
may also be constructed simply by single element risers.
Furthermore, a conduit 5 is arranged in connection with the space 6
created between the plurality of tiles 3 and the roof construction
2. The risers will only support corners of the tiles such that a
substantially free space 6 is created between the roof structure 2
and the tiles 3.
[0022] As the solar energy illustrated by the arrows 7 impacts on
the tiles 3 air trapped in the spaces 6 will be heated and thereby
move upwards through the perforations 8 provided in the tiles as
illustrated by the arrows 10. Consequently, an under-pressure will
occur in the space 6 whereby air will be sucked through the conduit
5 as illustrated by the arrow 9. By arranging the inlet 5' of the
conduit 5 in a suitable place where the air is cooler, for example
from a basement, cellar, ground well or a shadow section behind the
building 1, the air introduced into the spaces 6 due to the suction
created by the under-pressure will be substantially cooler and
thereby hinder the solar energy 7 in penetrating through the roof
structure 2 and into the building proper. In this manner a very
simple low-cost and no running cost cooling system is provided.
[0023] Further the outlet 5'' is provided with a valve 11. The
valve 11, is activated by a temperature sensitive mechanism, which
will not be further elaborated. Any suitable operation mechanism,
mechanical or electrical may naturally be employed. The valve
mechanism 11 may for example be programmed to be shut until the
temperature in the space 6 rises above 20 degrees, after which the
valve 11 opens and allows cool air to be sucked into the space
through the conduit 5.
* * * * *